Abimelech

Abimelech was the King of the Philistines of Gerar. When Abraham and Sarah moved to Gerar, Abraham told Abimelech that Sarah was his sister, leading to Abimelech seeking to take Sarah as his wife. However, God appeared to Abimelech in a dream and warned him against touching another man's wife; Abimelech confronted Abraham about his "lying". However, Abraham revealed that Sarah was also his half-sister, and Abimelech gave him gifts as an apology. He had a very similar situation with Isaac and Rebecca, discovering the true nature of their relationship after seeing Isaac "sporting" with Rebecca. Abimelech later sent Isaac away after he became too wealthy.